After a couple of rod holes started leaking behind a finished basement wall, we decided on a proactive campaign of basement waterproofing. We found several more rod holes either leaking or about to leak, but the most perplexing find was a sheet of bubble insulation glued and pinned to the concrete basement wall. It was clear that there was a problem behind there because the texture on the basement wall next to it was showing indications of water, so I ripped it down and found a cemented area that was visibly wet. The cement stops a little below the top of the basement wall, and there's a decent-sized crack visible there. Since I exposed the area a couple of months ago, the cement has remained damp to the touch.
I have two questions:
- What's going on? I'm assuming this was a crack in the basement wall that has been repaired, but how can the water be leaking through the cement?
- What should I do to fix it?
Photos:
Clarification: I need to fix this from the inside. Fixing it from the outside is not an option (due to money and practicality). Presumably I first need to remove the existing "fix". How should I do that? Then what's the best way to fix it "properly"? Any idea what's going on under the carpet?
Update: The plastic was part of a waterproofing solution by Foundation Systems of Michigan. It was leaking so I ripped the plastic off the wall. It turns out that it would have been under warranty if I hadn't touched it (not that there were any labels telling me it was under warranty or who to call; I called them for a quote on the repair and they happened to have done it in the first place). Now they want $1000 to fix it, but even if they were going to do it for free I don't trust them to fix it correctly after they've already gotten it wrong once. I can fix it myself better and cheaper.
What's going on under the carpet is that's where they've refilled with concrete after digging out the basement floor. Their "solution" is supposed to channel the water leaking in the crack down and out under the basement floor where it should get picked up by the interior drain tiles, dumped into the sump and pumped out. I don't like this "solution": I would think that having water leaking through the wall is eventually going to cause more problems (freeze-thaw cycles, particulates getting into the drain tiles), so I would rather keep the water out in the first place instead of redirecting it.
Best Answer
Water will always win if you "fix" these from the inside.
The correct, effective, and unfortunately expensive fix is to excavate outside and drain the water below wall level outside, then seal and drain the exterior of the wall to the exterior drain.
You may choose to chisel out this mess and try fixing from the inside again, but it will almost certainly fail again. The other inside approach is to "capture" the leak and lead it to a sump.
If tilting at the windmill, this image from "www.oldhouseweb.com" illustrates the correct shape for chiseling or diamond-blade cutting out the crack before attempting to re-fill it. At the bottom of their page they note that their information came from Michagan State University Extension publication E2109, and the image would appear to also have come from that publication originally.